test for wp_maybe_load_widgets

[pbearne]

Trac ticket: https://core.trac.wordpress.org/ticket/57201

[costdev]

Thanks for the PR @pbearne and for working to implement standards early to save time in reviewing / implementing review feedback! Much appreciated and look forward to seeing that in future PRs!

I've left some thoughts below which should help with an unmet standard (message parameter) and test stability. 🙂

[costdev]

A couple of thoughts:

1. Test methods with multiple assertions should have a message parameter to explain what went wrong.

For similar assertions (i.e. multiple assertion of class_exists()), the message can be:

• WP_Nav_Menu_Widget should not exist before doing something.
• WP_Nav_Menu_Widget should not exist after doing something.
• WP_Nav_Menu_Widget should exist after doing something.

2. It may be best to split this into two test methods:

• test_wp_maybe_load_widgets_should_respect_falsy_load_default_widgets_filter() - Use a data provider with falsy values to send to the filter hook via static closure, then assertFalse() for class_exists() and has_action().
• test_wp_maybe_load_widgets_should_load_widgets() - assertFalse() for class_exists() and has_action(), then call wp_maybe_load_widgets(), then assertTrue() on class_exists() and has_action() (all assertions should have the message parameter)

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[rejaulalomkhan]

Thanks for picking this up again and moving it to the new test structure, @pbearne! I ran it against trunk to check the open points from the earlier review:

Patch Testing Report

Patch tested: #3682 (head 1acb423)

Environment

• WordPress: 7.2-alpha-63166-src
• PHP: 8.3.35
• Server: wordpress-develop local Docker environment (nginx), PHPUnit 9.6.38
• Database: MySQL 9.7.2
• Browser: N/A (unit tests)
• OS: Windows 11
• Theme: N/A
• MU Plugins: None activated
• Plugins: None activated

Steps taken

1. Ran WpMaybeLoadWidgetsTest.php on single site and multisite: passes, but with 2 assertions. WP_Nav_Menu_Widget is already loaded during bootstrap, so the if ( ! class_exists( 'WP_Nav_Menu_Widget' ) ) branch never runs and the load_default_widgets path isn't covered.
2. Removed the test's own wp_maybe_load_widgets() call: the test still passes, since the class and the _admin_menu hook were both set up during bootstrap.
3. Made the function ignore the filter (if ( false ) instead of ! apply_filters( 'load_default_widgets', true )): the test still passes.
4. ❌ Patch is failing: the test passes regardless of what wp_maybe_load_widgets() does at call time.

Expected result

• The tests fail when the function stops hooking wp_widgets_add_menu, or when it ignores a falsy load_default_widgets.

Additional Notes

• The hook part can be tested by removing it first, since hooks are restored after each test. This also follows the split suggested in the earlier review (a falsy data provider for the filter):

  public function test_should_hook_widgets_menu() {
  	// The widgets library is loaded during bootstrap, so reset the hook first.
  	remove_action( '_admin_menu', 'wp_widgets_add_menu' );
  
  	wp_maybe_load_widgets();
  
  	$this->assertSame( 10, has_action( '_admin_menu', 'wp_widgets_add_menu' ) );
  }
  
  /**
   * @dataProvider data_falsy_values
   */
  public function test_should_not_hook_widgets_menu_when_filter_is_falsy( $value ) {
  	remove_action( '_admin_menu', 'wp_widgets_add_menu' );
  	add_filter(
  		'load_default_widgets',
  		static function () use ( $value ) {
  			return $value;
  		}
  	);
  
  	wp_maybe_load_widgets();
  
  	$this->assertFalse( has_action( '_admin_menu', 'wp_widgets_add_menu' ) );
  }
  
  public static function data_falsy_values() {
  	return array(
  		'false'        => array( false ),
  		'0'            => array( 0 ),
  		'empty string' => array( '' ),
  		'null'         => array( null ),
  	);
  }

  These pass on single site, multisite and with --order-by=reverse. Ignoring the filter fails 4 of the 5, and dropping the add_action() fails the first one. Loading default-widgets.php itself can't be checked this way, since the class is always loaded first.

• AI assistance: Claude Code (Claude Opus 5.5) was used to run the tests and draft the suggested tests; I reviewed the results.

[pbearne]

@rejaulalomkhan I have updated the dcode with your suggestions